The Hi-T Pigalert also known as ‘Pig Signaller’, ‘Pig
Detector’ & ‘Pig Passage Indicator’ is a bi-directional
intrusive devices attached to the pipeline via a Weld-on Base or Flange
and available up to ANSI 2500 (6170 psi). A trigger protrudes slightly
into the line enough to come into contact with a pig or sphere, but
have little to no effect on flow. All models are set with line specific
trigger lengths, but can be easily set to suit varying thicknesses
of pipeline of any diameter on site. Upon the pig or sphere striking
the trigger the Hi-T signals the user the pig has crossed the point
via a mechanically operated signal flag, electrical auto resetting
switch or both.

Hi-T units are classified in two styles: those models which are not designed
for removal while the line is under pressure and those models which are
fitted with an integral valve and suitable for controlled removal when
the pipeline cannot be de-pressurized. For these valve models a simple
jacking bracket tool is available for this purpose. Consisting of a safety
screw mechanism and bridging clamps it facilitates the removal and re-installation
of the Pigalert from the line under pressure in a matter of minutes.